Source Classification Categories are used to identify air pollution generating activities subject to standards under the CAA section 112(d). Together they represent 90 percent of the emissions of the 30 urban air toxics.

These North American Industry Classification System (NAICS) codes can be used to determine if your facility is subject to a specific Area Source NESHAP. If you have any questions regarding the applicability of the rules, please contact the appropriate DAQ Lead Contact listed above.